With a short history in elected office, Rep. Raul Ruiz (D-Palm Desert) is going to have to work especially hard to let residents of his 36th District know what he has done for them. All four embattled Democrats will need to figure out ways to win voters outside the party without alienating those within it to the point that they stay home on election day, a strategist said.

With a short history in elected office, Rep. Raul Ruiz (D-Palm Desert) is going to have to work especially hard to let residents of his 36th District know what he has done for them. All four embattled Democrats will need to figure out ways to win voters outside the party without alienating those within it to the point that they stay home on election day, a strategist said. (Don Bartletti, Los Angeles Times)

Jean Merl

At a recent reception in their honor, four of California's Democratic freshman House members posed for photos and beamed at well-wishers. But signs of the battles they face were hard to miss.

Asked by a fellow politician how his reelection campaign was going, Rep. Scott Peters of San Diego replied, "Hanging in. Got a tough race."

The same answer could have come from any of the honorees.

FOR THE RECORD: Congressional candidates: In the March 18 LATExtra section, an article about Democratic California House members who face tough reelection campaigns gave the first name of Republican Elizabeth Emken, who is challenging Rep. Ami Bera, as Susan. —

Although the rest of their first-term colleagues occupy seats in strongly Democratic districts, for these four, California's deep blue hue looks more like pale violet. Almost from the day they got elected, they have been in the sights of a Republican Party eager to reinforce its dominance in the House and reverse its low fortunes in the largely Democratic Golden State.

In the 2012 elections, Peters, Ami Bera of Elk Grove, Julia Brownley of Westlake Village and Raul Ruiz of Palm Desert captured seats held by the GOP that party leaders hope to win back this year.

Without a presidential race to spur Democratic turnout — historically lower than the GOP's in such elections — and with minuscule registration differences between the two major parties in their districts, the freshman Democrats know they've got their work cut out for them.

"The key will be what kind of opponents they end up with" in the fall, said Gary C. Jacobson, a UC San Diego political scientist. If those rivals are "Republicans who appeal to moderates, they will be formidable."

"The core Republican constituency in California tends to be pretty far to the right, so party leaders are going to have to throw their weight behind the most [broadly] attractive candidates" if they hope to prevail in the fall, Jacobson said.

In Bera's 7th District in the Sacramento suburbs, three Republicans are running: Susan Emken, an autism activist who made a lopsided challenge to Sen. Dianne Feinstein (D-California) in 2012; businessman and former congressman Doug Ose; and attorney Igor Birman, a top aide to Rep.Tom McClintock (R-Granite Bay), who has endorsed him.

Birman is generally viewed as the most conservative of the three and has drawn support from such groups as the Conservative Victory Fund and Gun Owners of America.

Peters, who narrowly ousted Republican Rep. Brian Bilbray in 2012, also has drawn three Republican challengers, in San Diego County's 52nd District. Former San Diego City Councilman Carl DeMaio is widely considered the strongest of the three.

The Peters campaign expects to square off with him in the fall. Trauma surgeon/businessman Fred J. Simon Jr. and military officer/businessman Kirk Jorgensen also are on the ballot.

DeMaio narrowly lost to former congressman Bob Filner in the San Diego mayor's race in 2012. He has been campaigning as a "new generation Republican," billing himself as fiscally conservative but moderate on social issues.

"He has very high name recognition, and he's getting national publicity as one of the few gay Republicans running," said Maryanne Pintar, who is taking a leave from her job heading Peters' district office to join the campaign.

"Scott has broad crossover appeal and he is the moderate in the race," Pintar said, adding, "We know it will be a tough race, but we feel good about" Peters' prospects.

Three Republicans and a candidate unaffiliated with any party are challenging Brownley for her Ventura County-based 26th District seat. Best known is Assemblyman Jeff Gorell of Camarillo, who is endorsed by House Majority Whip Kevin McCarthy and other prominent Republicans.

Unlike Brownley and Peters, Ruiz was a political novice when he beat Rep. Mary Bono Mack (R-Palm Springs) in 2012, a victory attributed to growing numbers of Latino voters, most of them Democrats.

This year, former state legislator Ray Haynes, a Republican, set up a same-party fight when he joined Assemblyman Brian Nestande of Palm Desert to challenge Ruiz, a former emergency room physician, in the 36th District.

With a short history in elected office, Ruiz is going to have to work especially hard to let residents know what he has done for them. In addition, he and the others must "make a case to voters they are a strong independent voice for their constituents," said Darry Sragow, a longtime Democratic strategist.

All four embattled Democrats will need to figure out ways to win voters outside the party without alienating those within it to the point that they stay home on election day, Sragow said.

Allan Hoffenblum, publisher of the California Target Book, which tracks elections, said the major parties won't decide where to put their resources until well after the primary.

"No one really knows what the temper of the times will be then, or who the [fall] candidates will be," Hoffenblum said.

On the flip side, Rep. David Valadao (R-Hanford) is the only freshman of his party who is in Democrats' sights. Amanda Renteria, former chief of staff to a Michigan U.S. senator, is on the national Democrats' list for early backing. And Democrat John Hernandez, who lost to Valadao in 2012, is running again in the Central Valley district, the 21st.